Behrend's been a 4 year school for quite a while (30 years to be exact) - it's NOT a branch like New Ken or DuBois. I believe it has some specialized programs that the Main campus doesn't offer. No it isn't as big as Main, but not everyone wants to go to a school that size.
I agree that community colleges or junior colleges would not be good places to have a fraternity - too much turnover - but that really doesn't have thing one to do w/ Behrend.